EP0034051B1

EP0034051B1 - Apparatus for inserting coils into core structure with inner and outer coil advancing means

Info

Publication number: EP0034051B1
Application number: EP81300499A
Authority: EP
Inventors: Tokuhita Hamane; Masaaki Tasai
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 1980-02-06
Filing date: 1981-02-05
Publication date: 1985-01-09
Also published as: DE3168089D1; JPS56112861A; EP0034051A1; US4383360A; JPS5910143B2

Description

The present invention relates to a coil insertion apparatus for inserting coils in respective grooves of a core structure.
Conventional coil insertion apparatus employ a jig having a plurality of coil guide paths formed by parallel guide members angularly spaced apart so that the guide paths align respectively with the grooves of a core structure which is mounted on the jig. A coil pusher is movably mounted inside the jig to advance the inner portions of the coils which have been manually inserted into the guide paths. An advancing mechanism is provided to move the pusher toward the core structure, so that the inner portions of the coils are forced into the core grooves. It is the usual practice that coils are inserted into the guide paths in a relatively horizontally tilted position to permit the inner portions of the coils to rest on the coil pusher to be effectively moved toward the core structure. However, due to the large difference in angular orientation between the core grooves and the coils being inserted thereinto, the coils tend to entangle with each other as they encounter the lower edges of the core structure, producing a substantial amount of friction to cause damages or scratches on the coils or deformation of the core structure.
According to the invention, there is provided a coil insertion apparatus for inserting loosely bundled coils respectively into grooves of a core structure through angulargly spaced-apart parallel guide paths of a jig by pushing inner portions of said coils with a pusher which is advanced in said jig toward said core structure by first moving means, characterised by coil holding means movably mounted externally of said parallel guide paths to engage outer portions of said coils and second moving means for causing said coil holding means to engage with said outer coil portions when said coil pusher initiates advancing said inner coil portions and for moving in coaction with the first moving means said coil holding means to advance said outer coil portions towards said core structure at substantially the same speed as that of the inner coil portions.
Preferably, upon engagement with the outer coil portions, the external coil holding device bears against the horizontally tilted outer coil portions to alter their orientations toward vertical positions so that the inner and outer coil portions are substantially aligned with the core grooves. In addition, due to the provision of the external coil holding means, the inner portions of the coils are moved under reduced pressure so that damages on the coils and other undesirable consequences are eliminated.
Preferably, the coil holding device comprises a pair of pivoted arms of identical construction which are rotatable in opposite directions to each other. The pivoted arms are normally in a horizontal position and rotated to a vertical position when the inner coil portions are started moving toward the core structure. Each pivoted arm is formed of a part-cylindrical portion and an upwardly turned end portion. The part-cylindrical portion of each arm bears against the outer coil sections so that the latter is depressed downwardly toward the jig and held in the upwardly turned end portion. The inner pusher and outer holding device coact each other in advancing the inner and outer portions of the coils to the core structure.
The invention will be further described with reference to the accompanying drawings, in which:

Fig. 1 is a front elevational, partially broken view of the coil insertion apparatus embodying the invention;
Fig. 2 is a plan view of the apparatus of Fig. 1;
Fig. 3 is a front view in elevation of a jig showing coils being mounted prior to an insertion operation;
Fig. 4 is a perspective view of a coil lifting arm of Figs. 1 and 2;
Fig. 5 is a view illustrating coils fully inserted into the grooves of a core structure on the jig; and
Fig. 6 is a perspective view of the core structure removed from the jig after inserting operation.

Referring now to Figs. 1 and 2, a coil inserting apparatus constructed according to the present invention is illustrated as generally comprising a lower stationary support 200, an upper stationary support 54, a vertically movable support 50 movable between the lower and upper support members 200, 54 and an external coil raising device 100 normally positioned a predetermined distance above the upper support 54 by a stopper 68 and arranged to be moved upward by an upward movement of the movable support 50. A pair of externally threaded rotary shafts 55 extend between upper and lower bearings 56 and 57 embedded respectively in the upper and lower support members 54 and 200 and is threadably engaged with a pair of internally threaded members 52 embedded in the movable support 50. The threaded rotary shafts 55 are operably coupled by pulleys 201, 202, 203 and belts 204 and 205 and by a worm gear arrangement 206 to the drive shaft of a motor 207 secured to the lower support 200 to move the support 50 vertically in opposite directions with respect to the upper and lower stationary supports 54 and 200. The verticaly movement of the movable support 50 is guided by means of a pair of guide shafts 53 of which the upper and lower ends are respectively connected to the upper and lower stationary supports 54 and 200 through bearings 51 secured to the support 50.
The external coil raising device 100 comprises a vertical support plate 101 and a horizontal support plate 61 which, as clearly shown in Fig. 2, has a semicircular cutout portion to accommodate a coil inserting jig 6 on a jig positioning device 11. To the horizontal support plate 61 is secured a pair of bolts 60 which extend downwardly through the upper stationary support 54 to carry a lift member 59 above a pair of stoppers or bolts 58 fixed to the movable support 50. The coil raising device 100 is moved upward by the movable support 50 when the stopper bolts 58 are brought into contact with the lift member 59 against springs 69. A pair of guide shafts 62 is secured to the upper stationary support 54 through bearings 63 secured to the horizontal support plate 61 to assist in smoothly moving the coil raising device 100 in opposite directions.
On the upper stationary support 54 is provided a push advancing rod guide block 49 having a plurality of vertically extending angularly spaced-apart parallel guide grooves 70 and a center guide opening through which a pusher advancing rod 7 extends. The lower end of the rod 7 is rigidly fixed to the movable support 50. Concentrically to the rod 7 is provided a plurality of vertically extending angularly spaced-apart wedge inserting members 8 which extend through an opening 47 of the lift member 59 respectively into the guide grooves 70 of the guide block 49 and are secured to the movable support 50 by a fixing block 44. The guide grooves 70 are in registry with vertical slots formed along the wedge guides of the jig 6 to align the wedge inserting members 8 with the wedge guide slots of the jig 6 for the purpose of inserting insulator wedges into respective grooves of a stator core 1 mounted on the jig 6.
Upper and lower proximity sensors or microswitches 74 and 75 are stationarily positioned with respect to the movable support 50 to provide a control signal to a hydraulic source 76 when their sensing fingers are operated by a contact member or dog 73 attached to an edge of the support 50.
The coil raising device 100 further comprises a hydraulically operated cylinder 71 supported by a bracket 102 to the vertical support plate 101 with its piston coupled to a rack 65 which is movably supported on a rack support 64 fixed to the vertical support 101. The hydraulic cylinder 71 is operated in response to a hydraulic pressure supplied from the source 76 to move its piston to an extended position when the upper proximity sensor 74 is activated during upward movement of the support 50. The cylinder piston is moved to the retracted position when the lower proximity sensor 75 is activated by downward movement of the support 50. Therefore, the rack 65 is moved to the right when the movable support 50 is raised to a point above the upper proximity sensor 74 and returns to the original position when the support 50 is lowered below the lower proximity sensor 75. Coil holding arms 57A and 57B of generally J-shaped elevational cross-section are mounted on respective pivot shafts 72A and 72B as clearly shown in Fig. 2. The pivot shafts 72A and 72B are journalled through respective bearings 67A and 67B which are secured to the support plate 101 and carry respective pinions 66A and 66B. The pinion 66B is in direct mesh with the rack 65, while the pinion 66A is in mesh with it via a second pinion 66A' so that the coil holding arms 57A and 57B are initially in a horizontal position as indicated by a chain-dot line in Fig. 1 and rotate in opposite directions to each other to a vertical position when the rack 65 is moved to the right.
The coil inserting jig 6 is of a conventional design. This jig includes a plurality of vertically extending angularly spaced-apart wedge guides 300 as shown in Fig. 3. As previously described, wedge guide slots are provided respectively along the length of the wedge guides 300 to permit insertion of insulator wedges into respective grooves of the stator core structure 1. A plurality of vertically extending guide blades 301 extend upwardly of the jig 6 and extend through the core structure 1.
In operation, a plurality of loosely bundled coils 4 are prepared and inserted respectively into coil guide paths formed between wedge guides 300 and guide blades 301 and secured at a point halfway from the bottom of the jib 6 in a substantially horizontally tilted position with the inner portions of the coils 4 resting on an internal coil pusher 302 and the remainder extending radially outwardly. A stator core holding member 12 is placed on the core structure 1 with a clamping plate 304 therebetween when the coil-mounted jig 6 is placed on the positioning device 11 of the coil insertion apparatus as shown in Fig. 1.
The motor 207 is energized to rotate the shafts 55 to lift the movable support 50 to an upward position so that the pusher advancing rod 7 and wedge inserting members 8 are raised together through the guide block 49. The pusher advancing rod 7 engages the pusher 302 of the jig 6 to advance it upwards and the wedge inserting members 8 are guided by blades 301 into alignment with the grooves of stator core structure 1. The upper proximity sensor 74 is then activated to move the rack 65 to the right from its original position whereby the pivoted coil holding arms 57A and 57B are rotated in opposite directions from the horizontal position to a vertical position where they engage the outwardly extending portions of the coils 4. More specifically, the vertically extending part-cylindrical portions 57' (see Fig. 4) of the holding arms 57A, 57B bear against the outer portions of the coils 4 to cause them to orient toward a vertical position and upwardly hold them in the upwardly turned lower end portions 57".
When the holding arms 57A, 57B are brought into vertical position, the bolts 58 of the moving support 50 engage the lifting plate 59 of the coil raising device 100 so that the coil holding arms 57A, 57B are raised to an upward position at the same speed as the pusher 302. Therefore, the inner and outer portions of the coils 4 are pushed upward at equal speeds. During this upward movement of the coils 4, the outer coil holding arms 57A, 57B coact with the inner pusher 302 to align the inner and outer portions of the coils toward the core structure 1 to achieve smooth insertion of coils 4 into the core grooves.
When the inner portions of the coils 4 extend through the core grooves and further upward as shown in Fig. 5, the motor 207 is deactivated. Simultaneously with the coil inserting operation, the wedge inserting members 8 move upward to insert insulator wedges (not shown) into the core grooves in a well known manner.
The motor 207 is subsequently operated by a reverse current to disengage the pusher advancing rod 7 from contact with the pusher 302 and to permit the coil raising device 100 to move downward under its own weight assisted by the springs 69 until it engages the stopper 68.
The support 50 is further moved downward activating the lower proximity sensor 75 to retract the cylinder 71. The coil holding arms 57A and 57B are turned to their original horizontal positions to permit the coil inserting jig 6 to be removed from the positioning device 11.
With the coils 4 being inserted, the core 1 is then removed from the jig 6. Fig. 6 is an illustration of the stator core structure 1 with the coils 4 being inserted into the grooves 3 of which the inner walls are fitted with insulators 2.
It is seen that with the assistance of the externally provided coil raising device 100 the inner portions of the coil 4 are guided into the stator core 1 with a reduced force so that scratches or damaging effects on the coil and deformation of the stator core structure are prevented.
Although in the foregoing description, the inner and outer portions of the coil 4 are raised at the same speed, they could also be raised at slightly different speeds to achieve the best result in so far as the inner and outer raising operations are effected during the same period of time. Furthermore, the external coil raising device 100 could also be modified so that it is constituted by more than two pivoted arms according to the structure of the stator core.

Claims

1. A coil insertion apparatus for inserting loosely bundled coils (4) respectively into grooves of a core structure (1) through angularly spaced-apart parallel guide paths of a jig (6) by pushing inner portions of said coils (4) with a pusher (302) which is advanced in said jig (6) toward said core structure (1) by first moving means (7, 50, 207), characterised by coil holding means (57A, 57B) movably mounted externally of said parallel guide paths to engage outer portions of said coils (4), and second moving means (71, 65, 66A, 66A', 66B, 76, 58, 59) for causing said coil holding means (57A, 57B) to engage with said outer coil portions when said coil pusher (302) initiates advancing said inner coil portions and for moving in coaction with the first moving means (7, 50, 207) said coil holding means (75A, 57B) to advance said outer coil portions towards said core structure (1) at substantially the same speed as that of the inner coil portions.

2. A coil insertion apparatus as claimed in claim 1, characterised in that said coil holding means (57A, 57B) comprise means (57') arranged to bear against said outer coil portions to orient said outer coil portions toward a vertical position and means (57") to hold said outer coil portions.

3. A coil insertion apparatus as claimed in claim 1 or 2, characterised in that said coil holding means (57A, 57B) comprises a pair of oppositely pivotable arms (57A, 57B) each having a part-cylindrical portion (57') and an upwardly turned end portion (57").

4. A coil insertion apparatus as claimed in claim 3, characterised in that said second moving means comprises means (66A, 66B, 66A') for rotating said arms (57A, 57B) from a horizontal position towards said vertical position in response to said coil pusher (302) substantially contacting said inner coil portions in and for moving said vertically positioned arms (57A, 57B) to advance said outer coil portions to said core structure (1 ).